Reaktion #155454

Reaktionsgleichung

(R)-tert-butyl 2-(3-cyclopentylureido)-2-phenylacetate

TFA

→

(R)-2-(3-cyclopentylureido)-2-phenylacetic acid

Ausbeute 64.2%

Lösungsmittel

CH2Cl2

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe volatile components were removed under reduced pressure
2. 2
   Sonstigethe crude product was recrystallized in ethyl acetate/pentanes

Vorschrift

To a stirred solution of (R)-tert-butyl 2-(3-cyclopentylureido)-2-phenylacetate (1.31 g, 4.10 mmol) in CH2Cl2 (25 mL) was added TFA (4 mL) and trietheylsilane (1.64 mL; 10.3 mmol) dropwise, and the resulting solution was stirred at room temperature for 6 hours. The volatile components were removed under reduced pressure and the crude product was recrystallized in ethyl acetate/pentanes to yield (R)-2-(3-cyclopentylureido)-2-phenylacetic acid as a white solid (0.69 g, 64%). 1H NMR (500 MHz, DMSO-d6) δ ppm 1.17-1.35 (m, 2H) 1.42-1.52 (m, 2H) 1.53-1.64 (m, 2H) 1.67-1.80 (m, 2H) 3.75-3.89 (m, 1H) 5.17 (d, J=7.93 Hz, 1H) 6.12 (d, J=7.32 Hz, 1H) 6.48 (d, J=7.93 Hz, 1H) 7.24-7.40 (m, 5H) 12.73 (s, 1H). LCMS: Anal. Calcd. for C14H18N2O3: 262.31. found: 263.15 (M+H)+. HPLC XTERRA C-18 3.0×50 mm, 0 to 100% B over 2 minutes, 1 minute hold time, A=90% water, 10% methanol, 0.2% H3PO4, B=10% water, 90% methanol, 0.2% H3PO4, RT=1.24 min, 100% homogeneity index.

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